What is buying power?

On JagSim you start with $100,000 in buying power. You buy $30,000 of stock, leaving $70,000. Sell $10,000 worth back and it rises to $80,000. Try to buy $90,000 of something and the order is rejected, you can't spend more than you have. Practicing this keeps you aware of how much dry powder is left for the next opportunity.

Buying power is the hard ceiling on what you can put to work at any moment, and beginners often forget it moves in real time as orders fill. Spend it all on one position and there's nothing left for the next idea or to add to what you own. In a cash account it's simply your uninvested cash, and it climbs back up as you sell. Practicing on a simulator that starts you with a fixed virtual balance makes the trade-off between one big bet and keeping some dry powder easy to feel.

Spending every dollar at once. Going all-in leaves nothing for a second opportunity or to average into a position, and it forces you to sell something else just to free up cash.

Forgetting pending orders tie cash up. A working buy order can reserve the cash it needs before it fills, so your available buying power may be lower than the balance you had in mind.

Confusing account value with buying power. Your total portfolio value includes positions you already hold. Only the uninvested part is what you can actually spend on something new.

Is buying power the same as my account balance?

In a simple cash account, your buying power is your uninvested cash. Your total account value also includes the current worth of stocks you already own, which you'd have to sell to spend.

Why did my buying power drop before a trade even filled?

A working buy order can set aside the cash it needs while it waits to execute, so that amount is held back until the order fills or gets cancelled.

Does buying power go back up when I sell?

Yes. Selling a position returns the proceeds to your available cash, which raises your buying power for the next trade. You can watch this update live on a paper simulator.